Kenworth T680 PACCAR MX-13 Forced Regen Required but Keeps Aborting

Question

My 2018 T680 just threw a high soot level warning and is threatening a 5 mph derate. I tried to start a parked regen twice, but it runs for about 10 minutes and then just cuts out with a 'Regen Aborted' message on the dash. I need to get this load to Chicago and can't go into full derate on the highway.

garagegrease · Accepted Answer

The issue turned out to be a completely clogged 7th injector (Hydrocarbon Doser Valve) and a failed DOC Temp Sensor. I pulled the doser (Part #2133306) and it was caked in carbon. I replaced the injector, installed a new temperature sensor, and performed a forced regen via software. Total cost for parts was about $485, and it successfully burned off the soot and cleared the derate. Make sure to torque the doser mounting bolts to 20 Nm.

obd2_owl · Answer

It could be a lazy 7th injector (Hydrocarbon doser). If those get carboned up, they don't spray a fine mist, and the flame goes out or never gets hot enough to sustain the burn. Try a fuel doser override test if you have DAVIE4 software.

Sarah Thompson · Answer

Check your DPF Inlet Temperature sensor readings using a scan tool. If the sensor is reading wonky or staying too low, the ECU won't allow the regen to continue because it thinks the face of the DOC isn't getting hot enough to oxidize the fuel.

backyard_bart · Answer

Have you looked at your EGR valve? If it's sticking open, you'll get too much inert gas in the combustion chamber, causing low exhaust temps that will make the aftertreatment system abort the regen for safety reasons.

Kenworth T680 PACCAR MX-13 Forced Regen Required but Keeps Aborting

Suggest a repair